You may use this process if you have completed a new Parents Worksheet for Child Support and it shows a change of 15% or more from the current amount OR if you have been served with a simplified modification petition and want to object. Use the free Online Child Support Calculator to produce a new Worksheet. If your current child support order is NOT from Arizona, you must modify child support in the state the order is from unless you register the child support order in Arizona and the Court accepts the registration.